MIAMI: Some cholesterol-lowering drugs, known as statins, appear to be linked to a lower risk of Alzheimer’s disease in certain people, suggested a study out Monday.

However, not all patients benefited, and the report stopped short of establishing any cause and effect, so experts said rigorous clinical trials are needed to further explore the issue.

The research in the Journal of the American Medical Association (JAMA) Neurology was based on an analysis of the medical records of nearly 400,000 people in the United States.

Researchers at the University of Southern California, Los Angeles examined use of the four most commonly prescribed statins: simvastatin, atorvastatin, pravastatin and rosuvastatin.

Black men saw no lower risk in Alzheimer’s disease associated with any statin.

But other racial and ethnic groups did, particularly if they were taking simvastatin, which was associated with a lower risk of Alzheimer’s for white, Hispanic and black women, and white and Hispanic men.

Atorvastatin was associated with a lower risk of Alzheimer’s among white, black, and Hispanic women and Hispanic men.

Both pravastatin and rosuvastatin were associated with reduced Alzheimer’s risk for white women.

Across the board, women saw a 15 percent lower risk of Alzheimer’s if they took statins, and men saw a 12 percent reduced risk.

Rosa Sancho, head of research at Alzheimer’s Research UK, urged caution in interpreting the results.

“Although this study highlights a link between statin use and a lower risk of Alzheimer’s, we can’t say from this research that statins can prevent the disease,” said Sancho, who was not involved in the study.

“Until there is firm evidence from clinical trials, we would not recommend people take statins for the purpose of preventing Alzheimer’s disease.”

High cholesterol is already a known risk factor for Alzheimer’s.

And some previous studies have suggested statins may have a protective effect against Alzheimer’s disease, the most common form of dementia.

“But these studies have produced mixed findings,” said Doug Brown, director of research and development at the Alzheimer’s Society.

“This new study goes some way towards clearing up this confusion by analyzing large amounts of existing data of people who use different types of statins over a long period of time,” he added.

“However, their data does not provide direct evidence that statins can influence dementia risk. This question will need to be answered by clinical trials.” --AFP